Equilateral triangle

Find the area of an equilateral triangle with a side of 15 cm.

Correct answer:

S =  97.4279 cm2

Step-by-step explanation:

a=15 cm  a2=(a/2)2+h2  S=a h2  S=34 a2=34 152=97.4279 cm2

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Pythagorean theorem is the base for the right triangle calculator.
See also our trigonometric triangle calculator.

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